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排序方式: 共有425条查询结果,搜索用时 15 毫秒
31.
C Beisland S Kolltveit BH Nilsen NH Hagness 《Canadian Metallurgical Quarterly》1998,118(12):1860-1862
Tetanus has become an uncommon disease in developed countries. Tetanus is caused by exotoxins from the bacteria Clostridium tetani. This microbe, which is obligate anaerobe, is present in soil, and animal and human faeces. The condition usually appears after contamination of wounds. However, reports have been published of tetanus occurring after both acute and selective gastrointestinal surgery. We present a case of severe postoperative tetanus in a 57 year-old woman who underwent bowel resection after strangulation of the ileum. The patient was treated on an intensive care unit and was artificially ventilated for 64 days. Seven months later she had fully recovered. Clinical presentation, diagnosis, treatment, and complications are discussed in the report. The diagnosis of tetanus is made by clinical observation. Nowadays, lack of suspicion of this condition may cause delay in administering proper treatment. Women and older men are often inadequately immunized. Doctors should therefore examine the immunization status of these groups of patients regularly. 相似文献
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Spectrophotometers, as electro-mechanical-optical devices, perform at a finite level of accuracy. This accuracy is limited by such factors as monochromator design, detector linearity, and cost. Generally, both the diagnosis and correction of spectrophotometric errors require a number of calibrated standard reference materials and considerable effort and commitment on the part of the user. A technique using multiple linear regression has been developed, based on the measurement of several suitably chosen standard reference materials, to both diagnose and correct systematic spectrophotometric errors, including photometric zero errors photometric linear and nonlinear scale errors, wavelength linear and nonlinear scale errors, and bandwidth errors. The use of a single chromatic ceramic tile to correct systematic errors improved the colorimetric accuracy of a set of chromatic and neutral tiles by a factor of two for a typical industrial-oriented spectrophotometer. Greater improvement can be achieved by increasing the number of tiles and performing a separate regression at each measured wavelength., These techniques have been extremely useful in improving inter-instrument agreement for instruments with similar geometry. 相似文献
34.
Coals from major Australian fields considered as suitable hydroliquefaction feedstocks were hydrogenated in a 1 kg h?1 continuous reactor unit at reaction conditions 415–435 °C and 21 MPa using a stirred flow reactor with retention time of about 2 h. The effect of coal rank and the catalytic effects of disposable iron-based (red mud plus sulphur) catalysts were studied. The system was operated continuously with process-derived recycle solvent for up to 236 h. The time for a single pass of recycle solvent was estimated to be 20 h. Distillate oil yields in the range 35–53% on daf coal were obtained under catalytic operation. The heavier product oils were shown to contain predominantly aromatics, hydroaromatics and phenolics. This indicates that fairly severe hydro-treatment would be required to produce specification diesel and aviation turbine fuels. Recycle solvent composition was observed to stabilize in 2–4 passes after making a process change. These data compare favourably with those obtained on the same coals in larger pilot plants showing that this unit is capable of producing useful yield data. 相似文献
35.
P Aavitsland O Nilsen V Hasseltvedt A Lystad 《Canadian Metallurgical Quarterly》1996,116(29):3493-3498
Up to 1996, a total of 1,537 individuals had been reported as having HIV infection in Norway (population 4.3 million). 511 of these had developed AIDS and 410 had died from AIDS. 223 persons had acquired HIV heterosexually. Less than a fifth of these had acquired the infection from persons who themselves had been infected with HIV heterosexually in Norway. Named testing of pregnant women, recruits and blood donors confirms the limited spread of HIV. We estimate that the annual incidence of heterosexually acquired HIV infection has remained at 20-30 for the last ten years. Earlier prognoses for the epidemic in Norway were grossly erroneous, mainly owing to lack of knowledge about the factors determining the spread of HIV. Given the low rate of transmission of the virus and the sexual behaviour of Norwegians, there was never any real danger of a large heterosexual HIV epidemic in this country. The future efforts to combat the epidemic should focus on maintaining features that make Norwegian society less vulnerable to HIV. 相似文献
36.
Joel?B.?Lebret M.?Grant?NortonEmail author David?F.?Bahr David?P.?Field Kelvin?G.?Lynn 《Journal of Materials Science》2005,40(13):3347-3353
Single crystals of Nd:YVO4 grown with the Czochralski technique frequently exhibit light scattering defects that are detrimental to their lasing and optical properties. Defects in the form of low angle grain boundaries have been characterized in what are nominally ‘single crystals’. The misorientation angles of the boundaries were determined to be typically < 1°, which corresponds to formation energies of approximately 1 Jm−2. It was found that dislocations generated during crystal growth and cooling have enough mobility in certain growth directions to form low angle grain boundaries through polygonization. Despite the relatively high energies the boundaries were stable, being immobile at annealing temperatures up to 97% of the melting point (2083 K). Suggestions are made to reduce or eliminate polygonization, including the addition of atoms with a size either much larger or smaller than Y3+. 相似文献
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Information from full-scale fire tests are gathered and systemised. The knowledge from these tests is used as input to three different models, ranging from a simple spreadsheet model to advanced computational fluid dynamics (CFD) modelling, for calculating the temperature in the smoke layer. The deviation between the fire tests and the computed results is described and an evaluation of how this may influence the use of the models is discussed from the point of view of risk analysis. 相似文献
40.
Vidar Kveldsvik Amir M. Kaynia Farrokh Nadim Rajinder Bhasin Bjørn Nilsen Herbert H. Einstein 《International Journal of Rock Mechanics and Mining Sciences》2009,46(4):686-698
The seismic stability of the Åknes rock slope, western Norway, was analysed by using the distinct element code UDEC (Universal Distinct Element Code). The slope poses a threat to the region as a sudden failure may cause a destructive tsunami in the fjord. The dynamic input was based on earthquakes with return periods of 100 and 1000 years, and in most models the input shear wave was a harmonic function (sine wave). Models with depths of the sliding surface up to 200 m and with ground water conditions derived from site investigations were analysed, as well as models with ground water conditions assumed from possible future draining of the slope. The analyses indicate that an earthquake with a return period of 1000 years is likely to trigger sliding to great depth in the slope at the present ground water conditions and that the slope will be stable if it is drained. The analyses also indicate that sliding is not likely to be triggered by an earthquake with a return period of 100 years at the present ground water conditions. 相似文献